Gilman’s reagents

H347). The reaction of Gilman s reagent, R2CuLi, also involves ligand coupling. There are many examples of hypervalent iodine compounds. 

These complexes are obtained by the action of LiPh or MgPh2 on Cul or CuBr. The type of compound formed depends on the Cu Li(Mg) ratio and on the solvent. In the case of methyl compounds, depending on the ratio of CuX(CuMe) to LiMe, various complexes are formed which remain in equilibrium. Gilman s reagent, LiCuMe2, the best known and most commonly utilized organometallic compound of copper, is considerably more complex than can be judged by its stoichiometric composition. 

Confirmation that cw-addition of alkyl copper complexes occurs in these reactions has been obtained by studies of lanthanide-induced shift H n.m.r. spectra of the products. Corey has now introduced (3-methyl-3-methoxybut-l-ynyl)copper in THF as a relatively inexpensive reagent for the generation of mixed cuprates (Gilman s reagents), which enable coupling reactions to occur in high yield with alkyl-lithium reagents. ... 

Organocopper compounds used for carbon-carbon bond formation are called Gilman reagents in honor of Henry Gilman who first stud led them Gilman s career in teaching and research at Iowa State spanned more than half a century (1919-1975)... 

Gilman s test for the presence of Grignard reagent is useful about 0.5 ml. of the ethereal solution is removed with a capillary dropping tube and treated with an equal volume of a 1% solution of Michler s ketone in dry benzene and then, slowly, with 1 ml. of water. Addition of several drops of a 0.2% solution of iodine in acetic acid then produces a characteristic greenish blue color if Grignard reagent was present. 

Determination of the concentration of Grignard reagents is often important for their further preparative use and is best effected by titration with acid as elaborated by Gilman s school 112... 

This conviction found further strong support in Gilman s tremendous authority in the field of organometallic chemistry. His method to prepare allylic Grignard reagents eventually led to the commercial availability of allylmagne-sium halides in diethyl ether and tetrahydrofuran solutions ... 

The sense of the asymmetric induction at the /J-carbon of 10 is opposite to that of 7, indicating that 10 reacts with the Gilman reagents in a conformation where the carbonyl is s-trans to the a,(i double bond to avoid steric repulsion of the a-substituent and the camphor residue. 

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